278 OTT. [Vol. VII. 



For a further proof that the very small oil-globules in the 

 intestinal cells were directly due to the worms feeding upon 

 the milk, a number of worms was divided into two lots. One 

 lot was fed with milk as before, while the other lot was not fed. 

 Both lots were treated with chrom-osmic-acetic acid, stained with 

 alum, carmine, and sectioned. When these sections were com- 

 pared, the intestinal cells of the worms which had been fed the 

 milk contained many more oil-globules than the cells of the 

 worms which had not been fed. Two cells of a worm which had 

 been fed contained each twenty-two and sixteen oil-globules, 

 while two cells from the same locality of a worm which was not 

 fed contained each ten and nine oil-globules. These worms 

 were in the milk less than an hour. 



My observations agree with those of Graber ('79, p. 278) and 

 Graff ('75, p. 414; '82, p. 258) as to the form of the intestinal 

 cells after they have been crushed from a living animal, but do 

 not agree with those of Graff upon the form of the cells as 

 they are seen in their natural condition in sections. In this 

 condition these cells are not cylindrical as described by Graff, 

 but club-shaped, as described by Bohmig ('90, p. 234) for 

 Plagiostoma and Cylindrostoma. 



As to the behavior of the isolated intestinal cells, I am able 

 to confirm the observations of Du Plessis ('74) on Plagiostoma 

 Lemani, Metschnikoff ('78, p. 388) on Mesostoma Ehrenbergii, 

 Graber ('79, p. 278) on Stenostoma leucops, and von Ihering 

 ('80) on Graffilla imuicicola ; and also those of Metschnikoff as 

 to the difference between the size of the cells in a worm which 

 has been recently fed and one that has not been fed. 



Bohmig ('90, p. 235) saw in Plagiostoma Girardi and Cylin- 

 drostoma Klostermannii pseudopodia-like protoplasmic processes 

 protruded and retracted, and at times fused into a mass. 

 He says (p. 236) : " Es ist bekannt, das die Darmzellen von 

 Microstoma, Stenostoma, und Macrostoma Cilien tragen. Nicht 

 unwahrscheinlich ist es mir, das diese Cilien, ich mochte sagen, 

 Starr gewordene Plasmafortsatze sind wie wir sie bei den 

 Alloiocoelen wahrnehmen." 



Speaking of the function of the intestinal cells of Plagiostoma 

 Girardi and Cylindrostoma Klostermannii he says : " Die Funk- 

 tion dieser plasmatischen Fortsatze ist leicht zu verstehen : 

 sie werden ahnlich wie die Pseudopodien und pseudopodien- 



